This invention relates to sulfonated alkylphenoxy alkanoic acids containing 2-5 carbons in the acid moiety and their salts, and to the use of these compounds as dye levelers in dyeing synthetic polyamide textiles with acid dyes to alleviate barre.
In dyeing synthetic polyamide textiles such as fibers, fabrics, or garments (hereafter collectively called "nylons" or "nylon textiles") with acid dyes, there often is obtained barre or streakiness in the dyed textile due to inherent physical and/or chemical differences existing in the yarns from which the textile has been made. For further information about the causes and manifestations of barre reference is made to U.S. Pat. No. 3,619,122 and American Dyestuff Reporter, Feb. 12, 1968, pgs. 42-47.
To prevent or minimize barre to an acceptable degree, a variety of anionic surfactants have been employed as dye levelers in the dyeing of nylon textiles with acid dyes. One of the earliest class of anionic surfactants used were the mixed fatty alcohol sodium sulfates. Subsequently, alkyl sulfonate and alkyldiaryl sulfonate surfactants were recommended. More recently, more complex anionics have been alleged to prevent barre, for example: sulfonated sulphones derived from a variety of hydroxy-substituted aryl compounds in U.S. Pat. No. 3,536,438, dialkyl sulfosuccinates in U.S. Pat. No. 3,619,122, alkane-or alkene-amido-benzene-sulphonics in U.S. Pat. No. 3,713,768, and monosulfonated alkylphenoxy glycerol in U.S. Pat. No. 3,809,717. Also, alkyl-substituted diphenyl ether sulfonates, believed to have the general formula shown in U.S. Pat. No. 3,127,441, have been used.
In spite of the abundance of work done to identify anionic surfactants capable of minimizing or preventing barre, a need still exists for new dye levelers considering the great number of different acid dyes employed, the fact that they are typically used in combinations, and the variety of nylons textiles being dyed. In many instances less-than-satisfactory barre effects are tolerated because a dye leveler suitable from both an economic and a performance standpoint is unavailable.